docs: def check_dependee_exists(self, depender, dependee, dependee_id):
  		"""Checks whether a depended-on module is available.
  		"""
  		shutit_global.shutit_global_object.yield_to_draw()
  		# If the module id isn't there, there's a problem.
  		if dependee is None:
  			return 'module: \n\n' + dependee_id + '\n\nnot found in paths: ' + str(self.host['shutit_module_path']) + ' but needed for ' + depender.module_id + '\nCheck your --shutit_module_path setting and ensure that all modules configured to be built are in that path setting, eg "--shutit_module_path /path/to/other/module/:."\n\nAlso check that the module is configured to be built with the correct module id in that module\'s configs/build.cnf file.\n\nSee also help.'
  		return ''